Chock for aircraft and other vehicles



March 2, 1948. M. J. MADISON 2,437,108

CHOCKS FOR AIRCRAFT AND'OTHER VEHICLES Filed June 27,1945 2 Sheets-Sheet 1 I 251 J If 2 lfai'fzmlflhdzsammvzm'ola aWRNEY March 1948- I M. J. MADISON 2,437,1(93

CHOCKS FOR AIRCRAFT AND OTHER VEHICLES Filed June" 27, 1945 I 2 Shets-Sheet ,2

lzzzrzz'mrjz 'mon v 'mvEmoR' Patented Mar. 2, 1948 STATES ElN-T OFFICE Martin J. Madison, teen, N. 0'. Application June 21; 1945; Serial'No. eons-a The object of the invention is to provide: improvements in checks forautomotive vehicles, but more especially for airpianes and: the like-,andlat; the same time: to providea double chock that is particularly adapted for use with military planes in association with: aircraft carriers,v where the: roll and pitch" of the ship makes it mandatory to chock a planeswheels both fore and aft in, order to prevent it fromxrolllng. in either direction until under its own power; also to providea simple and eificient means for attaching skis toan airplane, wherebya shift from Wheelsto skis may be made by the pilot oroth'er crew-members during flight: and likewise to providechocks se cured to'the: landing gear of a plane and thereby operative to prevent theft'of and joy; hopping in such plane.

Practically if. not all chucking of airplanes is at present efiected by meansof -'wooden;- blocks or the like, that are placed in front'ofaplanes wheels-at an airport, or both: in front and to the rear of a plane's-wheels upon aca'rriers deck, thus making it necessary for one or more persons other than the crew aboard the ship to check and-;unchock the ship from without, asmereapplication of a planes brakes has been foundinsumciently positive to prevent its unintentional movement, as for instance in; a heavy winder when a carriers deck is slanting at an excessive angle. in'a rough sea. 7

When the brakes alone are. applied, the only factor resisting the movementiof the plane upon a-supporting surface is the friction of. but a small portionof the peripheral surface of-its tires withsaid supporting surface, and under certain. extreme conditions this has been found to be insufflcient for purposes of full. safetmwherefore the customary-chocksareemployedAhereby placing actual obstacles-in the way of the wheels, to avoid which itv would. be necessary for the plane.

to climb over the check against the additional.

are simultaneously actuated into operative and V inoperative'posi'tions by a single motion ot the pilot or other individual aboard the plane. I V

' A .further object" is toip-rovi de a, double check 6v Clalmm- (01.188-5) iorreach wheel of a plane; comprisingv chock-incimembers that oifena; minimum of resistanceto; the:- flow-ofi airpast" them cliningfiight, and that are: adapted" to: simultaneously move radially off the adjacent wheel inzangularly related directionst. so" as. to: approach" the: surface supporting.- the plane: welle in: advance and: to therear of. a: point vertically. beneath the axis of said wheel;

Still-tancther-objectis'to provide a chock. of this natuzewh-ich iszclosely' associated with the transverse overall: width of the; wheel and tire, and: there-15y projects'therefrom only aminimum dis-- tance; Whilewbeing composed of. relatively, few" parts and'tthese' o'tthe simplest form and; opera tion I Withvtheiolijects. thus briefl; stated, the imventionucompcisesiiurther details of construction and operation', that are hereinafter fully brought, out] in the following? description; when read. in cor-ijunctionv with the accompanying. drawings, in; which 1. is an inboard side elevation of an airplane wheelwi-th one embodiment of the im proved. double-chock operatively associated there-- and shownrin'retracted position; Fig; 2 isa similar view but showing the checking membc'na ofithe improved: chock in extended operative positions; isan. exploded view showing the principal parts otthe: device unassembled but in: alignment forxnormal' assembly; Fig. 4 is an: enlarge'd transverse vertical section through the. axis-of the device and adjacent wheel, as shown: imFi -t l, the several parts of thedevice. being as-- sembled in: greater separation than in actual practice in order toshowthe construction, and.

. operation more c1early ;,.and Figs 5 is an elevational view of; one of the chock members per se.

Referring: tothe drawings, it is considered unnecessary to illustrate a complete airplane or otherrform of air transportwhich is supported by and-upon wheels whenat rest, and so the entire plane orsimilar vehicle-1s symbolically represent" ed-i merely: by a. fragmentary portion of astud orthe. likento: which. is secured. in any suitable. manner anaxla member. 2,? which is principally composed. "of enlaitge'dl body portion 3,, from whichaxiall'y extends aweducadshaft portion 4, upon which is. notataloly mounted the usual wheel; 5 carrying the tire. 51. It will. be understood that. theti're. audits-mounting perse are merely represented; schematically, as. their exact form andf arrangement comprises no part of the invention and in view of"whichi fact noneof the customary anti-friction hearings: and their housing. are

shown, 7 V I The saidv axle. memberxfurthercomprises a: plurality of angularly related, radially extending arms 1, respectively provided with reinforced heads 8, while to the inner enlarged portion of said member there is preferably integrally secured a suitable bored enlargement 9, b means of which any desired form of mechanism may be connected to said member as for tilting the through and being rotatable slidably within an aperture I3 in a plate M, which is secured by bolts to the head portions 8 of the respective radial arms 1 of said stud. To an upper portion of said plate there is secured a short stud l5 upon which is rotatably mounted a small gear or pinion it that meshes with the larger gear H, and which through any desired ratchet or other suitable medium I! is connected to a torque tube l8, having one or more universal joints l9. By this arrangement, the pilot or another individual within the cabin of 'a plane or other vehicle is able either manually or by means of an electric actuator to rotate the gears l6 and II and thereby the elongated gear [2, which, by referring to Fig. 4, will be seen as extending well through the aperture l3 in said plate l4,.and'

into meshed engagement with the rack teeth 20, which line one side or edge only ofan elongated slot 2| in each of the chock members 22, each of which members is preferably provided with transversely enlarged feet 23, adapted to directly engage the deck of a carrier, the ground at an airport, or other surface upon which the vehiclemay be resting, so that, regardless of surface level or firmness of terrain, air pressures in tires and other factors, the new device effects secure" and positive chocking.

It should be noted that the said feet 23 may be of any shape and transverse extent, but that they should be in such relative positions and alignment that together they oifer a minimum or drag while the vehicle is in flight. Each of 25 is a disc gear 26 providedwith axially pro-i jecting notches 21 (or circumferentially spaced radial holes) carried by a cylindrical flange 28. This disc gear is secured 'by suitable bolts 29 and spacers 30 to the hub portion 3i of the Wheel 5, as clearly indicated in Fig. 4. It will be noted that each of .the chock members is provided upon its outboard surface with a longitudinally extending boss or spur 32, which when its supporting member is in extended position engages between a pair of adjacent notches (or within a radial hole), so as to thereby prevent rotation of the wheel 5 and its tire 6.

I With a construction such as that described, and the several parts in the retracted positions shown in Fig. 1, rotation of the torque tube 18,

either manually or through an electric actuator,

by one within or carried by the plane or other vehicle or from outside of the same, if preferred, operates to rotates the gears I6, II and i2, thereby shifts the chock members 22 longitudinally downwardly and outwardly until their feet 23 engage the surface upon which the vehicle may be resting, and in which extended positions the spurs 32 are caused to engage between .pairs of notches 21 (or in a hole) upon the circular rack or gear 28, to thereby lock said wheel and prevent further rotation of the tire 6. Re-

. verse rotation of said torque tube similarly causes said chock members to be retracted into the positions shown in Fig. 2 while at the same time Withdrawal'of the spurs from engagement with saidnotches 21 (or from a hole in flange 28) instantly permits the wheel and tire to rotate freely.

From this description it is clear that a broad principle of vehicle-carried chocks is involved, and that the details of construction and operation of a single embodiment, such as that shown in the drawings, is of relatively secondary importance, since many mechanisms are conceivable by which said principle may be put into practice for more or less efficient operation.

Having thus described my invention, what I claim and desire to protect by Letters Patent of the United States is:

1. The combination of a vehicle frame, a wheel rotatably carried by said frame, a pair of chocking members also carried by "-said'frame and restrained to move in paths angularly related to each other and radially with respect to said wheel, and means to simultaneouslyshift said members into extended and re tractedjposition's.

- 2. The combination of a vehicle frame, a wheel rotatably carried by said frame, a pair'of chocking members also carried by said frame and restrained against movement other than radially of said wheel, each of said members having a set of rack teeth, a gear in mesh with and common to both setsof teeth, and means supported by said frame for remote simultaneous'actuation of saidmembers selectively into extended and retracted positions by a person also supported by said frame.

3. The combination of an axle, a vehicle wheel rotatably carried thereby, a circular arrangement of irregularities carried by and concentric with said wheel, a stationay plate, a pair of chock members reciprocatable in angularly related paths, means carried by said plate to ,limitmovement ofsaid members to'their respective paths,- each member, being, provided with aset of rack teeth, a gearrotatably carried by said axle and engaging said rack teeth. to reciprocate said members alternatelyin opposite directions, and a spur carried by one of said members and engageable with said irregularitieswhenitssupporting member is in extended position to prevent' rotation ofsaid wheel.

4. The combination of an axle, a

bers reciprocatable in angularly related paths;

a stationary plate carried by said axle, mens carried by said plate to restrict movement of said members to their respective paths, and actuating means to concurrently reciprocate said mem bers alternately in opposite directions.

5. The combination of an axle, a vehiclewheel rotatably carried thereby, a. pair of elongated chock members having elongated apertures vehicle wheel rotatably carried thereby, a pair of chock memthrough which said axle extends and a set of rack teeth upon one side of each of said apertures, a plate fixed with respect to said axle, means carried by said plate to limit movement of said members to angularly related, downwardly divergent paths, a gear carried by said axle and simultaneously engaging said rack teeth, and means to rotate said gear in opposite directions from a remote position, to shift said members into engagement with the surface upon which said wheel rests or to retract said members into inoperative position within the radial limits of said wheel.

6. The combination of an axle, a vehicle wheel rotatably carried thereby, a pair of elongated chock members having elongated apertures through which said axle extends and a set of- REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,423,846 Frederick July 25, 1922 2,171,352 Beavon Aug. 29, 1939 FOREIGN PATENTS Number Country Date 262,168 Great Britain Dec. 9, 1926 

